Police believe a woman found dead in her apartment just south of the Hall of Justice early Tuesday had been killed.

And her ex-boyfriend has been arrested on suspicion of the crime.

It started about 4 a.m., when a 36-year-old man’s relatives drove to the police station to say he was at his apartment near 32nd and O streets allegedly threatening suicide, Assistant Police Chief Jim Peschong said.

When officers arrived, he said, Cesar Fermeli Penado was trying to hang himself.

They took him into custody.

In talking with him, officers became concerned about his ex-girlfriend’s welfare, Peschong said.

They soon discovered Maria Rosario Moreno’s body in the bedroom of her third-floor apartment at 830 S. 10th St.

The 38-year-old’s neck had been cut, Peschong said.

Moreno’s death came as a shock to Dan Koch, owner of Affinity Production Co., where she started working, through a temp agency, a year and a half ago.

“She was a very nice woman,” he said. “And an unbelievably hard worker.”

Moreno always seemed cheerful, Koch said. She worked her 10-hour shifts and never complained as she packed bags of Weaver’s and store-brand potato chips, popcorn and cheese puffs into boxes.

When she didn’t show up for her shift Tuesday morning, Koch thought she was sick. He figured they would hear from her.

She had told friends and co-workers she was afraid of her ex-boyfriend and considered getting a restraining order, Koch said. Court records don’t indicate she had such an order.

During her shift Monday, she seemed her normal self.

“We never thought this would happen,” he said.

Rochelle Sandford, who sits at the front desk, said fellow employees had worried about her.

It was hard to imagine something could happen to the woman who sat so serenely under a tree to read during lunch breaks.

Moreno always made sure to say goodbye at the end of the day.

“It hit us all very hard,” she said. “She had a lot of friends here.”

Ernest Herrera, 80, who lives in Moreno’s building, said though he never saw Penado, he heard he had come over a couple of months ago and tried to start trouble with Moreno.

Herrera met Moreno one time when they were both sitting on the back porch at the apartment building, he said.

“She was a pleasant little girl, as far as I’m concerned,” he said.

Peschong stopped short of describing Penado as a suspect in Moreno’s killing at a news conference at 9 a.m. Tuesday but said investigators were talking with him.

By early afternoon, police had booked him into jail on suspicion of first-degree murder and use of a weapon to commit a felony.

Prosecutors had not formally charged Penado, though he was expected to be in court this afternoon.

Penado told police his relationship with Moreno had deteriorated and that angered him, Peschong said.

Penado drove to Moreno’s apartment early Tuesday and forced his way into the building, Peschong said. Penado tried to strangle Moreno before using a knife to cut her throat, he said.

The killing is the second in Lincoln this year.

Reach Lori Pilger at 473-7237 or lpilger@journalstar.com. Staff writer Hilary Kindschuh contributed to this report.